Conventionally, emulsion fuel is known as the fuel that water and oil which are crushed to fine particles and mixed each other. And, in order to increase fuel combustion efficiency, the emulsion fuel has been used for a large-sized boiler or a ship engine and the like. And, various kinds of mixing apparatuses have been invented for making the emulsion fuel. Further, the above mixing apparatuses are used in order to crush various kinds of fluids finely and to mix them uniformly. And, the fuel which are crushed and mixed like this are used in a factory and the like.
The above prior mixing apparatus includes a single rotation unit which is mounted in a case and is rotated by a motor, and a fixing unit which is mounted in the case parallel to the rotation unit. Here, at the facing side of the rotation unit and the fixing unit, a plurality of projections are formed along the circumferential direction at a predetermined interval so that they form concentric circles which are alternately engaged with each other.
Accordingly, if a fluid, that is, a raw material is supplied in the center of the rotation unit which is rotating at a high speed, the liquid is rotated along the projections of the rotation unit so that it passes the spaces between the respective projections owing to centrifugal force and is outwardly discharged through the discharge holes formed at the periphery of the case. Then, the liquid alternately passes the respective arrays of the projections of the rotation unit and the fixing unit so that it continuously collides with the respective projections. Accordingly, the fluid is crushed to fine particles and mixed together so that it is emulsified in fine particles.
However, the mixing apparatus has the problem that, if the fluid supplied in its center passes between the rotation unit and the fixing unit, because it is rapidly discharged through the discharge holes of the case or is discharged toward the outside through a centrifugal vane, the fluid may not be crushed to particles of desirous size. Accordingly, the mixing apparatus has the problem that much troubles may be caused and much time is wasted because the user stores the emulsified fluid in a tank and emulsifies the fluid once again in order to crush the fluid to desirous size. Further, the mixing apparatus has the problem that additional equipments are increased and the emulsified material may be separated each other and returned to the original state while it is stored in the tank.
Accordingly, in case of emulsifying the fluid by the prior mixing apparatus, an emulsifier like a surface active agent is usually mixed into the fluids in order that the supplied fluids may be mixed uniformly and the mixed fluids may not be easily separated each other. However, the emulsification method like the above has the problems that the cost is increased and the environment is polluted because an emulsifier like a surface active agent may be additionally required besides pure fuel or raw material, and the emulsion fuel may be separated into water and oil while preheating the fuel.
And, the fluid supplied into said mixing apparatus is rotated along the rotation unit in the spaces between the projections of the rotation unit so that it flows outwardly because of centrifugal force at the moment that the spaces between the projections of the rotation unit are opened to the spaces between the projections of the fixing unit. Here, while said fluid is going to flow toward the tangential direction of the rotation unit because of centrifugal force, the spaces between the projections of the fixing unit filled with said fluids may radially form the rectangular spaces which are different angle from the flowing direction of the fluids. Accordingly, the fluid flown in the rectangular space may be resisted in its acceleration movement, and the emulsification efficiency may be remarkably decreased.
Further, because the respective projections of the mixing apparatus are made by forming a plurality of concentric ring type protrusions on one surface of a disk and by slitting said protrusions toward the radial direction, the size of the projections grows larger toward the outer side of the radial direction. Accordingly, the mixing apparatus has the problem that the efficiency of crushing and mixing is decrease remarkably when the fuel passes the spaces between the projections so that the capacity may not be easily increased.